This is a multi-center, open-label, one-year study to evaluate the activity and safety of the protease inhibitor indinavir sulfate (MK-0639) administered in combination with the nucleoside analogue inhibitors of reverse transcriptase zidovudine (ZDV) and lamivudine (3TC) for the treatment of acute HIV infection. These newly infected subjects harbor virus with the least genetic diversity and are therefore most likely to be drug responsive. Twelve subjects were enrolled at this site, and 11 remain in the trial. The study is now closed to accrual. All subjects, if eligible, will be allowed to participate in a one-year extension and then, if still eligible, for yearly extensions indefinitely thereafter. The drug therapy in the extension phase of this study will remain unchanged: MK-0639 at 800 mg q8h, ZDV at 200 mg q8h, and 3TC at 150 mg BID. Safety will be assessed as well as antiviral activity, which will be determined by serial measurements of plasma RNA and cell-associated virus, as measured by quantitative co-culture.